I use DigitalOcean... almost all their products support IPv6. Only floating IPs are IPv4, but can work around that by not destroying droplets so the IPv6 address doesn't change.
One annoyance I have is that IPv6 is disabled on VMs (droplets) by default. So every time you upgrade your Kubernetes cluster and it recreates every node they all have no IPv6 again with no way to change this. In the end I couldn't be bothered and just stopped rebooting every node after every update.